Acryloyl chitosan as a macro-crosslinker for freezing-resistant, self-healing and self-adhesive ionogels-based multicompetent flexible sensors.

Here, a polysaccharide derivative acryloyl chitosan (AcCS) is exploited as macro-crosslinker to synthesize a novel ionogel poly (acrylic acid-co-1-Vinyl-3-butyl imidazolium chloride) (AA-IL/AcCS) via a one-pot method. AcCS provides abundant physical and chemical crosslinking sites contributing to the high mechanical stretchability (elongation at break 600 %) and strength (tensile strength 137 kPa) of AA-IL/AcCS. The high-density of dynamic bonds (hydrogen bonds and electrostatic interactions) in the network of ionogels enables self-healing and self-adhesive features of AA-IL/AcCS. Meanwhile, AA-IL/AcCS exhibits high ionic conductivity (0.1 mS/cm) at room temperature and excellent antifreeze ability (-58 °C). The AA-IL/AcCS-based sensor shows diverse sensory capabilities towards temperature and humidity, moreover, it could precisely detect human motions and handwritings signals. Furthermore, AA-IL/AcCS exhibits excellent bactericidal properties against both gram-positive and gram-negative bacteria. This work opens the possibility of polysaccharides as a macro-crosslinkers for preparing ionogel-based sensors for wearable electronics.

Correlation Analysis of Estrogen Levels and Psychological Status Among Patients with Uterine Fibroids.

Objective: This study aims to investigate the correlation between estrogen levels and psychological distress, focusing on depression and anxiety symptoms among patients diagnosed with uterine fibroids. Methods: The study employed a retrospective design and enrolled a cohort comprising 50 patients diagnosed with uterine fibroids and 50 healthy individuals as controls. Serum estradiol levels were quantified using a chemiluminescent immunoassay technique one month before surgery in the patient group. Depression and anxiety levels were evaluated using the Self-Rating Depression Scale (SDS) and the Self-Rating Anxiety Scale (SAS), respectively. Results: Significant differences in SDS scores, SAS scores, and serum estradiol levels emerged between the patient and control groups (P < .05). Patients exhibited higher SDS and SAS scores alongside elevated serum estradiol levels. Correlation analysis unveiled a negative association between SAS scores and estrogen levels among patients (r = -0.724, P = .013), suggesting a rise in anxiety levels with declining estrogen levels. Similarly, a negative correlation surfaced between SDS scores and estrogen levels among patients (r = -0.624, P = .016), indicating increased depressive symptoms as estrogen levels decrease. Conversely, no noteworthy correlations were demonstrated between anxiety or depressive symptoms and estrogen levels in the control group. Conclusion: Reduced estrogen levels were linked to heightened anxiety and depressive symptoms in patients with uterine fibroids. These findings suggest a plausible connection between estrogen hormone levels and psychological well-being, particularly concerning anxiety and depression. Further exploration of this association is warranted to shed light on potential therapeutic interventions targeting hormonal regulation to improve psychological distress in affected individuals.

Glycosylase-based base editors for efficient T-to-G and C-to-G editing in mammalian cells.

Base editors show promise for treating human genetic diseases, but most current systems use deaminases, which cause off-target effects and are limited in editing type. In this study, we constructed deaminase-free base editors for cytosine (DAF-CBE) and thymine (DAF-TBE), which contain only a cytosine-DNA or a thymine-DNA glycosylase (CDG/TDG) variant, respectively, tethered to a Cas9 nickase. Multiple rounds of mutagenesis by directed evolution in Escherichia coli generated two variants with enhanced base-converting activity-CDG-nCas9 and TDG-nCas9-with efficiencies of up to 58.7% for C-to-A and 54.3% for T-to-A. DAF-BEs achieve C-to-G/T-to-G editing in mammalian cells with minimal Cas9-dependent and Cas9-independent off-target effects as well as minimal RNA off-target effects. Additional engineering resulted in DAF-CBE2/DAF-TBE2, which exhibit altered editing windows from the 5' end to the middle of the protospacer and increased C-to-G/T-to-G editing efficiency of 3.5-fold and 1.2-fold, respectively. Compared to prime editing or CGBEs, DAF-BEs expand conversion types of base editors with similar efficiencies, smaller sizes and lower off-target effects.

Predictors of successful salvage microdissection testicular sperm extraction (mTESE) after failed initial TESE in patients with non-obstructive azoospermia: A systematic review and meta-analysis.

BACKGROUND: There has been no systematic review and meta-analysis to analyze and summarize the predictive factors of successful sperm extraction in salvage microdissection testicular sperm extraction. OBJECTIVES: We aimed to investigate the factors predicting the result of salvage microdissection testicular sperm extraction in patients with non-obstructive azoospermia who failed the initial microdissection testicular sperm extraction or conventional testicular sperm extraction. MATERIALS AND METHODS: We conducted a systematic literature search in PubMed, Web of Science, EMBASE, and the Cochrane Library for literature that described the characteristics of patients with non-obstructive azoospermia who underwent salvage microdissection testicular sperm extraction after failing the initial microdissection testicular sperm extraction or conventional testicular sperm extraction published prior to June 2022. RESULTS: This meta-analysis included four retrospective studies with 332 patients with non-obstructive azoospermia who underwent a failed initial microdissection testicular sperm extraction and three retrospective studies with 177 non-obstructive azoospermia patients who underwent a failed conventional testicular sperm extraction. The results were as follows: among non-obstructive azoospermia patients whose first surgery was microdissection testicular sperm extraction, younger patients (standard mean difference: -0.28, 95% confidence interval [CI]: -0.55 to -0.01) and those with smaller bilateral testicular volume (standard mean difference: -0.55, 95% CI: -0.95 to -0.15), lower levels of follicle-stimulating hormone (standard mean difference: -0.86, 95% CI: -1.18 to -0.54) and luteinizing hormone (standard mean difference: -0.68, 95% CI: -1.16 to -0.19), and whose testicular histological type was hypospermatogenesis (odds ratio: 3.52, 95% CI: 1.30-9.53) were more likely to retrieve spermatozoa successfully, while patients with Sertoli-cell-only syndrome (odds ratio: 0.41, 95% CI: 0.24-0.73) were more likely to fail again in salvage microdissection testicular sperm extraction. Additionally, in patients who underwent salvage microdissection testicular sperm extraction after a failed initial conventional testicular sperm extraction, those with testicular histological type of hypospermatogenesis (odds ratio: 30.35, 95% CI: 8.27-111.34) were more likely to be successful, while those with maturation arrest (odds ratio: 0.39, 95% CI: 0.18-0.83) rarely benefited. CONCLUSION: We found that age, testicular volume, follicle-stimulating hormone, luteinizing hormone, hypospermatogenesis, Sertoli-cell-only syndrome, and maturation arrest were valuable predictors of salvage microdissection testicular sperm extraction, which will assist andrologists in clinical decision-making and minimize unnecessary injury to patients.

Fenofibrate suppresses the progression of hepatoma by downregulating osteopontin through inhibiting the PI3K/AKT/Twist pathway.

Primary hepatic carcinoma (PHC) is a leading threat to cancer patients with few effective treatment strategies. OPN is found to be an oncogene in hepatocellular carcinoma (HCC) with potential as a treating target for PHC. Fenofibrate is a lipid-lowering drug with potential anti-tumor properties, which is claimed with suppressive effects on OPN expression. Our study proposes to explore the molecular mechanism of fenofibrate in inhibiting HCC. OPN was found extremely upregulated in 6 HCC cell lines, especially Hep3B cells. Hep3B and Huh7 cells were treated with 75 and 100 µM fenofibrate, while OPN-overexpressed Hep3B cells were treated with 100 µM fenofibrate. Decreased clone number, elevated apoptotic rate, reduced number of migrated cells, and shortened migration distance were observed in fenofibrate-treated Hep3B and Huh7 cells, which were markedly abolished by the overexpression of OPN. Furthermore, the facilitating effect against apoptosis and the inhibitory effect against migration of fenofibrate in Hep3B cells were abolished by 740 Y-P, an agonist of PI3K. Hep3B xenograft model was established, followed by treated with 100 mg/kg and 200 mg/kg fenofibrate, while OPN-overexpressed Hep3B xenograft was treated with 200 mg/kg fenofibrate. The tumor growth was repressed by fenofibrate, which was notably abolished by OPN overexpression. Furthermore, the inhibitory effect of fenofibrate on the PI3K/AKT/Twist pathway in Hep3B cells and Hep3B xenograft model was abrogated by OPN overexpression. Collectively, fenofibrate suppressed progression of hepatoma downregulating OPN through inhibiting the PI3K/AKT/Twist pathway.

A phase 1 study of dimdazenil to evaluate the pharmacokinetics, food effect and safety in Chinese healthy subjects.

Background and objective: As a partial positive allosteric modulator of the gamma-aminobutyric acid A (GABAA) receptor, dimdazenil was used for the treatment of insomnia with the potential to alleviate associated side effects compared to full agonists. The objective of this trial is to assess the safety, tolerability, food effect and pharmacokinetics following single and multiple doses of dimdazenil in Chinese healthy subjects. Methods: In this phase 1 trial, 36 healthy subjects aged ≥18 years were assigned to receive a single dose of 1.5, 2.5, or 5 mg dimdazenil, with each dose cohort consisting of 12 subjects, and 14 subjects were assigned to receive a multiple 2.5 mg daily dose of dimdazenil for 5 days. Safety, tolerability, and pharmacokinetic characteristics were evaluated. Results: Of the 50 subjects enrolled and 49 completed the trial, the incidences of treatment-emergent adverse events (AEs) in the single-dose groups of 1.5, 2.5, and 5 mg were 16.7%, 58.3% and 66.7% respectively, while 61.5% in the multiple-dose group. There were no serious AEs, deaths, AEs leading to discontinuation or AEs of requiring clinical intervention in any treatment groups. The most treatment-emergent AEs were dizziness (n = 4, 8.2%), hyperuricemia (n = 2, 6.1%), upper respiratory tract infection (n = 2, 6.1%), diastolic blood pressure decreased (n = 2, 6.1%), blood TG increased (n = 2, 6.1%) and RBC urine positive (n = 2, 6.1%). All AEs were mild-to-moderate and transient, and no severe AEs were documented in any study phase. The PK profile of dimdazenil and its active metabolite Ro46-1927 was linear across 1.5-5 mg oral doses in humans. The median Tmax for dimdazenil was in the range of 0.5-1.5 h, and the apparent terminal t1/2z ranged from 3.50 to 4.32 h. Taking Dimdazenil with food may delay Tmax and decrease Cmax, without affecting the total exposure (AUC). No relevant accumulations of dimdazenil and Ro 46-1927 were observed in multiple-dose group. Conclusion: Dimdazenil was generally well tolerated in healthy Chinese subjects after single and 5 days-multiple dosing. The pharmacokinetic properties of dimdazenil are compatible with a drug for the treatment of insomnia. Clinical Trial Registration: chinadrugtrials.org.cn, identifier CTR20201978.

Mechanically Robust and Flame-Retardant Superhydrophobic Textiles with Anti-Biofouling Performance.

The attachment of bio-fluids to surfaces promotes the transmission of diseases. Superhydrophobic textiles may offer significant advantages for reducing the adhesion of bio-fluids. However, they have not yet found widespread use because dried remnants adhere strongly and have poor mechanical or chemical robustness. In addition, with the massive use of polymer textiles, features such as fire and heat resistance can reduce the injuries and losses suffered by people in a fire accident. We developed a superhydrophobic textile covered with a hybrid coating of titanium dioxide and polydimethylsiloxane (TiO2/PDMS). Such a textile exhibits low adhesion to not only bio-fluids but also dry blood. Compared to a hydrophilic textile, the peeling force of the coated textile on dried blood is 20 times lower. The textile's superhydrophobicity survives severe treatment by sandpaper (400 mesh) at high pressure (8 kPa) even if some of its microstructures break. Furthermore, the textile shows excellent heat resistance (350 °C) and flame-retardant properties as compared to those of the untreated textile. These benefits can greatly inhibit the flame spread and reduce severe burns caused by polymer textiles adhering to the skin when melted at high temperatures.

Impact of target-mediated drug disposition on hetrombopag pharmacokinetics and pharmacodynamics in Chinese healthy subjects and patients with chronic idiopathic thrombocytopenic purpura.

AIMS: The pharmacokinetics (PK) of hetrombopag were found to be nonlinear across evaluated dose ranges. The aim of this study was to develop a mechanism-based population pharmacokinetic/pharmacodynamic (PopPK/PD) model and to provide a reasonable expected therapeutic dose for a future confirmatory clinical study of hetrombopag. METHODS: Nonlinear mixed-effects modelling was performed using pooled 2168 hetrombopag concentrations and 1526 platelet counts from 72 healthy subjects and 32 chronic idiopathic thrombocytopenic purpura (ITP) patients from two phase I studies and one phase II study. The final model was evaluated via goodness-of-fit plots, visual predictive check and nonparametric bootstrap. Simulations from the validated PopPK/PD model were used to devise an expected therapeutic dose for later confirmatory clinical study. RESULTS: The pharmacokinetic data of hetrombopag were well described by a modified target-mediated drug disposition (TMDD) model with dual sequential first-order absorption. Mean parameter estimates (interindividual variability) were CL/F 7.66 L/h (63.5%), Vc /F 30.0 L (77.2%) and Kdeg 0.693/h (87.1%). The pharmacodynamic profile was well described by a five-compartment lifespan model with four-transit and one-platelet compartments. Simulation results suggested that chronic ITP patients following 10 mg once-daily hetrombopag would able to achieve an ideal platelet count level (50-200 × 109 /L). CONCLUSION: TMDD was the primary reason leading to nonlinear PK profile of hetrombopag. Our PK/PD modelling and simulation results support 10 mg once-daily as the recommended therapeutic dose for chronic ITP patients in subsequent confirmatory clinical study of hetrombopag.

Pharmacokinetics and Bioequivalence of a Generic Fixed-Dose Combination Tablet of Metformin Hydrochloride/Vildagliptin Versus a Branded Product in Healthy Chinese Subjects Under Fed and Fasting Conditions.

The purpose of this study was to compare the bioequivalence and safety of test and reference preparations of fixed-dose combination tablets of metformin hydrochloride/vildagliptin 850 mg/50 mg in healthy volunteers under fasting and fed conditions for marketing authorization in China. A single-dose, randomized, open-label, 2-way crossover study was conducted. Blood samples were collected up to 36 hours after dosing in each period with a 7-day washout. Pharmacokinetic parameters, including maximum plasma concentration (Cmax ), time to reach Cmax , area under the plasma concentration-time curve (AUC) from time 0 to the last time point of the measurable concentration, AUC from time 0 to infinity, terminal elimination half-life, and apparent clearance, were calculated using noncompartmental methods and compared between the 2 formulations. Safety profiles were assessed, including significant findings of vital signs, electrocardiogram, laboratory tests, physical examination, and adverse events. A total of 30 healthy subjects (19 men, 11 women) were randomized, and 29 subjects were treated under fasting conditions. Likewise, 30 subjects (24 men, 6 women) were randomized and treated under fed conditions. The geometric mean ratio and corresponding 90% confidence intervals of Cmax , AUC from time 0 to the last time point of the measurable concentration , and AUC from time 0 to infinity for both metformin hydrochloride and vildagliptin between the 2 fixed-dose combination formulations were within the bioequivalence acceptance range of 80% to 125% under fasting or fed conditions. Therefore, the generic and branded formulations were bioequivalent and well tolerated in healthy Chinese subjects.

Impacts of Immunometabolism on Male Reproduction.

The physiological process of male reproduction relies on the orchestration of neuroendocrine, immune, and energy metabolism. Spermatogenesis is controlled by the hypothalamic-pituitary-testicular (HPT) axis, which modulates the production of gonadal steroid hormones in the testes. The immune cells and cytokines in testes provide a protective microenvironment for the development and maturation of germ cells. The metabolic cellular responses and processes in testes provide energy production and biosynthetic precursors to regulate germ cell development and control testicular immunity and inflammation. The metabolism of immune cells is crucial for both inflammatory and anti-inflammatory responses, which supposes to affect the spermatogenesis in testes. In this review, the role of immunometabolism in male reproduction will be highlighted. Obesity, metabolic dysfunction, such as type 2 diabetes mellitus, are well documented to impact male fertility; thus, their impacts on the immune cells distributed in testes will also be discussed. Finally, the potential significance of the medicine targeting the specific metabolic intermediates or immune metabolism checkpoints to improve male reproduction will also be reassessed.

Carbon Nanotube-Hydrogel Composites Facilitate Neuronal Differentiation While Maintaining Homeostasis of Network Activity.

It is often assumed that carbon nanotubes (CNTs) stimulate neuronal differentiation by transferring electrical signals and enhancing neuronal excitability. Given this, CNT-hydrogel composites are regarded as potential materials able to combine high electrical conductivity with biocompatibility, and therefore promote nerve regeneration. However, whether CNT-hydrogel composites actually influence neuronal differentiation and maturation, and how they do so remain elusive. In this study, CNT-hydrogel composites are prepared by in situ polymerization of poly(ethylene glycol) around a preformed CNT meshwork. It is demonstrated that the composites facilitate long-term survival and differentiation of pheochromocytoma 12 cells. Adult neural stem cells cultured on the composites show an increased neuron-to-astrocyte ratio and higher synaptic connectivity. Moreover, primary hippocampal neurons cultured on composites maintain morphological synaptic features as well as their neuronal network activity evaluated by spontaneous calcium oscillations, which are comparable to neurons cultured under control conditions. These results indicate that the composites are promising materials that could indeed facilitate neuronal differentiation while maintaining neuronal homeostasis.

Resveratrol acts via melanoma-associated antigen A12 (MAGEA12)/protein kinase B (Akt) signaling to inhibit the proliferation of oral squamous cell carcinoma cells.

The present study examined how resveratrol affects cell growth and MAGEA12/Akt signaling pathway in OSCC cells. Cal-27 cells were transiently transfected with a plasmid encoding MAGEA12, and the effects of overexpression were assessed in terms of cell viability, colony formation and the epithelial-mesenchymal transition. Cal-27 cells and MAGEA12-overexpressing cells were treated with resveratrol, then the cell viability and colony formation were also assessed by CCK8 assay and microscope, respectively. Levels of MAGEA12, p-Akt, Akt, Cyclin D1, and CDK14 genes and these proteins were analyzed using quantitative reverse-transcription polymerase-chain reaction and western blot. In the present research, we first generated and transiently transfected MAGEA12 plasmid into Cal-27 cells. Our results suggested that overexpressing MAGEA12 led to an increase in levels of phospho-Akt, which was associated with increased cell viability, colony formation. Moreover, overexpressing MAGEA12 also resulted in the up-regulation of Cyclin D1 and CDK14, indicating MAGEA12 induces the cell proliferation of Cal-27 cells. In addition, these effects were partially reversed by inhibiting Akt. Furthermore, resveratrol could inhibit the proliferation and colony in Cal-27 cells and decrease the expressions of MAGEA12 and p-Akt depending on the time and concentration. These effects were also partially reversed by MAGEA12 overexpression and Akt activation. In summary, resveratrol may suppress the growth of OSCC cells by inactivating MAGEA12/Akt signaling. These findings suggest that resveratrol may be a therapeutic drug for OSCC in clinical.

Multi-omics reveals a relationship between endometrial amino acid metabolism and autophagy in women with recurrent miscarriage†.

Deterioration of the endometrial environment is an essential cause of recurrent miscarriage (RM). However, current studies in terms of endometrial amino acid metabolic characterization and autophagy are still inadequate. We tried to (1) identify the alternation in metabolite profiles in the RM endometrium; (2) investigate the expression of autophagy-related proteins in RM; and (3) elucidate the association between amino acid metabolism and autophagy in RM. Our results showed that glutamine metabolites were up-regulated in the endometrium of RM women. The levels of autophagy-associated proteins, LC3B, ATG12, and Beclin-1, were significantly higher in RM. Hemostasis, autophagy and IFNα signaling were the top three differentially activated signaling pathways between women with RM and normal pregnancy. Interestingly the expression of AMPK and GCN2 was significantly up-regulated in the endometrium of women with RM, and the same expression trend was also observed in the human endometrial stromal cells cultured in glutamine deprivation medium. Furthermore, inhibition of AMPK decreased the level of GCN2, indicating a positive correlation between GCN2 and AMPK. The expression of GCN2 was consistent with the expression of ATG12 and beclin-1; however, it was opposite to that of p62. Exposure to glutamine deprivation increased the level of LC3B, GCN2, ATG12, and beclin-1. Altogether, these findings suggested significant crosstalk between amino acid metabolism and autophagy. In summary, our data suggested that aberrant crosstalk between amino acid metabolism and autophagy may contribute to the impaired endometrial microenvironment of RM. Our study may provide new insight into the diagnosis of RM due to endometrial factors.

Manipulating the position of DNA expression cassettes using location tags fused to dCas9 (Cas9-Lag) to improve metabolic pathway efficiency.

BACKGROUND: Deactivated Cas9 (dCas9) led to significant improvement of CRISPR/Cas9-based techniques because it can be fused with a variety of functional groups to form diverse molecular devices, which can manipulate or modify target DNA cassettes. One important metabolic engineering strategy is to localize the enzymes in proximity of their substrates for improved catalytic efficiency. In this work, we developed a novel molecular device to manipulate the cellular location of specific DNA cassettes either on plasmids or on the chromosome, by fusing location tags to dCas9 (Cas9-Lag), and applied the technique for synthetic biology applications. Carotenoids like ß-carotene serve as common intermediates for the synthesis of derivative compounds, which are hydrophobic and usually accumulate in the membrane compartment. RESULTS: Carotenoids like ß-carotene serve as common intermediates for the synthesis of derivative compounds, which are hydrophobic and usually accumulate in the membrane components. To improve the functional expression of membrane-bound enzymes and localize them in proximity to the substrates, Cas9-Lag was used to pull plasmids or chromosomal DNA expressing carotenoid enzymes onto the cell membrane. For this purpose, dCas9 was fused to the E. coli membrane docking tag GlpF, and gRNA was designed to direct this fusion protein to the DNA expression cassettes. With Cas9-Lag, the zeaxanthin and astaxanthin titer increased by 29.0% and 26.7% respectively. Due to experimental limitations, the electron microscopy images of cells expressing Cas9-Lag vaguely indicated that GlpF-Cas9 might have pulled the target DNA cassettes in close proximity to membrane. Similarly, protein mass spectrometry analysis of membrane proteins suggested an increased expression of carotenoid-converting enzymes in the membrane components. CONCLUSION: This work therefore provides a novel molecular device, Cas9-Lag, which was proved to increase zeaxanthin and astaxanthin production and might be used to manipulate DNA cassette location.

A visualized clinical model predicting good quality blastocyst development in the first IVF/ICSI cycle.

RESEARCH QUESTION: Is it possible to establish a visualized clinical model predicting good quality blastocyst (GQB) formation for patients in their first IVF/intracytoplasmic sperm injection (ICSI) cycle? DESIGN: A total of 4783 patients in their first IVF/ICSI cycle between January 2015 and December 2019 were retrospectively included and randomly divided into the training set (n = 3826) and the testing set (n = 957) in an 8:2 ratio. The least absolute shrinkage and selection operator (LASSO) regression was adopted to select the most critical predictors for GQB formation to construct a visualized nomogram model based on the data of patients in the training set. Receiver operating characteristic and calibration curves were used to evaluate the predictive accuracy and discriminative ability. The performance of the model was also validated on independent data from patients treated in the testing set. RESULTS: Maternal age, maternal serum anti-Müllerian hormone (MsAMH) concentration and the number of oocytes retrieved were highlighted as critical predictors of GQB development and were incorporated into the nomogram model. Based on the area under the curve (AUC) values, the predictive ability for ≥1, ≥3 and ≥5 GQB were 0.831, 0.734 and 0.748, respectively. The calibration curve also showed high concordance between the observed and predicted results. The AUC for predicting ≥1, ≥3 and ≥5 GQB in the testing set were 0.805, 0.695 and 0.707, respectively, which were similar to those for the training set. CONCLUSIONS: The visualized nomogram model provides great predictive value for GQB development in patients in their first IVF/ICSI cycle and can be used to improve clinical counselling.

A programmable CRISPR/Cas9-based phage defense system for Escherichia coli BL21(DE3).

Escherichia coli BL21 is arguably the most popular host for industrial production of proteins, and industrial fermentations are often plagued by phage infections. The CRISPR/Cas system is guided by a gRNA to cleave a specific DNA cassette, which can be developed into a highly efficient programable phage defense system. In this work, we constructed a CRISPR/Cas system targeting multiple positions on the genome of T7 phage and found that the system increased the BL21's defense ability against phage infection. Furthermore, the targeted loci on phage genome played a critical role. For better control of expression of CRISPR/Cas9, various modes were tested, and the OD of the optimized strain BL21(pT7cas9, pT7-3gRNA, prfp) after 4 h of phage infection was significantly improved, reaching 2.0, which was similar to the control culture without phage infection. Although at later time points, the defensive ability of CRISPR/Cas9 systems were not as obvious as that at early time points. The viable cell count of the engineered strain in the presence of phage was only one order of magnitude lower than that of the strain with no infection, which further demonstrated the effectiveness of the CRISPR/Cas9 phage defense system. Finally, the engineered BL21 strain under phage attack expressed RFP protein at about 60% of the un-infected control, which was significantly higher than the parent BL21. In this work, we successfully constructed a programable CRISPR/Cas9 system to increase the ability of E. coli BL21's to defend against phage infection, and created a resistant protein expression host. This work provides a simple and feasible strategy for protecting industrial E. coli strains against phage infection.

Nonclassical Biofilms Induced by DNA Breaks in Klebsiella pneumoniae.

Biofilms usually form when the density of bacteria increases during the middle to late periods of growth in culture, commonly induced by quorum-sensing systems. Biofilms attach to the surfaces of either living or nonliving objects and protect bacteria against antibiotics and a host's immune system. Here, a novel type of biofilm (the "R-biofilm") is reported. These biofilms were formed by clinically isolated Klebsiella pneumoniae strains following double-stranded-DNA breaks (DSBs), while undamaged bacteria did not form classic biofilms even in the later stages of growth. R-biofilms had a fixed ring-like or discoid shape with good ductility and could protect many living bacterial cells within. We show that extracellular proteins and DNAs released, probably by dead bacteria, were the core structural materials of R-biofilms. We anticipate that novel signaling pathways besides the bacterial SOS response are involved in R-biofilm formation. The observations in this study suggest a limitation to the use of the currently popular Cas9-mediated bactericidal tools to eliminate certain bacteria because the resulting DSBs may lead to the formation of these protective R-biofilms.IMPORTANCE Many pathogenic bacteria can form biofilm matrices that consist of complex molecules such as polysaccharides, proteins, and DNA. These biofilms help the bacteria to infect and colonize a host. Such biofilms may attach and develop on the surfaces of indwelling medical devices or other supportive environments. This study found that following double-strand breaks in their DNA, Klebsiella pneumoniae cells can form a novel type of biofilm with ring-like or discoid morphology. This biofilm structure, named the "R-biofilm," helps protect the bacteria against adverse conditions such as exposure to ethanol, hydrogen peroxide, and UV radiation.

miR-146a promotes proliferation, invasion, and epithelial-to-mesenchymal transition in oral squamous carcinoma cells.

Epithelial-to-mesenchymal transition (EMT) is key to invasion and metastasis by oral squamous carcinoma (OSCC) cells. MicroRNAs (miRNAs) such as miRNA-146a are known to be upregulated in OSCC. However, it is unclear whether they are involved in driving EMT. Here, we investigated the effect of miR-146a overexpression on proliferation, migration, and EMT in OSCC cells. OSCC cells were transfected with a plasmid expressing miR-146a precursor. Cell lines that stably overexpressed miRNA-146a were assessed for proliferation, colony formation, and invasiveness in vitro. Expression of markers and regulators of EMT, cell motility, and invasion were measured by qRT-PCR and western blot. Potential miRNA-146a binding sites in the 3'UTR of ST8SIA4 were identified by bioinformatic analysis. To confirm that miRNA-146a binds to and regulates ST8SIA4, we transfected OSCC cell lines with miRNA-146a mimics and a luciferase reporter construct containing either the wild type or mutant 3'UTR of ST8SIA4. OSCC cell lines that overexpressed miR-146a displayed higher proliferation, colony formation, invasion, and MMP-2 activity than cells transfected with a control vector. Overexpression of miR-146a also decreased expression of the epithelial cell marker E-cadherin and increased expression of Twist1, a transcription factor that promotes EMT, as well as markers associated with mesenchymal cells (vimentin and N-cadherin) and tumor invasion (p-paxillin and p-cortactin). Luciferase expression was lower in OSCC cells transfected with miRNA-146a mimics or with luciferase constructs carrying the wild type, but not mutant, 3'UTR of ST8SIA4. Overexpression of miR-146a promotes EMT phenotypes and may drive tumorigenesis and progression in OSCC, making it a useful target for future OSCC treatments.

Elastic Superhydrophobic and Photocatalytic Active Films Used as Blood Repellent Dressing.

Durable and biocompatible superhydrophobic surfaces are of significant potential use in biomedical applications. Here, a nonfluorinated, elastic, superhydrophobic film that can be used for medical wound dressings to enhance their hemostasis function is introduced. The film is formed by titanium dioxide nanoparticles, which are chemically crosslinked in a poly(dimethylsiloxane) (PDMS) matrix. The PDMS crosslinks result in large strain elasticity of the film, so that it conforms to deformations of the substrate. The photocatalytic activity of the titanium dioxide provides surfaces with both self-cleaning and antibacterial properties. Facile coating of conventional wound dressings is demonstrated with this composite film and then resulting improvement for hemostasis. High gas permeability and water repellency of the film will provide additional benefit for medical applications.

Nomogram for predicting the risk of bone metastasis in breast cancer: a SEER population-based study.

BACKGROUND: Bone is the most common metastasis site of breast cancer. The prognosis of bone metastasis is better than other distant metastases, but patients with skeletal related events (SREs) have a poor quality of life, high healthcare costs and low survival rates. This study aimed to establish an effective nomogram for predicting risk of bone metastasis of breast cancer. METHODS: The nomogram was built on 4,895 adult/female/primary invasive breast cancer patients with complete clinicopathologic information, captured by the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015. Five biological factors (age, grade, histologic type, surgery of breast lesions and subtypes) were assessed with logistic regression to predict the risk of bone metastases. The predictive accuracy and discriminative ability of the nomogram were determined by the Receiver Operating Characteristic (ROC) curves and the calibration plot. Results were validated on a separate 2,093 cohort using bootstrap resampling from 2010 to 2015 as an internal group and a retrospective study on 120 patients in the First Affiliated Hospital of China Medical University from 2010 to 2014 at the same situation as an external group. RESULTS: On multivariate logistic regression of the primary cohort, independent factors for bone metastases were age, grade, histologic type, surgery of breast lesions and subtypes, which were all selected into the nomogram. The calibration plot for probability of incidence showed good agreement between prediction by nomogram and two observations. The ROC curves presented a good statistical model for risk of bone metastasis, and the corresponding AUC value of the development group, internal validation group and external validation group were 0.678, 0.689 and 0.704 respectively. CONCLUSIONS: The proposed nomogram resulted in more-accurate prognostic prediction for breast cancer patients with bone metastases.