Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 225
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
ChemMedChem ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677239

RESUMO

Host Defense Peptides (HDPs) have gained considerable interest due to the omnipresent threat of bacterial infection as a serious public health concern. However, development of HDPs is impeded by several drawbacks, such as poor selectivity, susceptibility to proteolytic degradation, low-to-moderate activity and requiring complex syntheses. Herein we report a class of lipo-linear α/urea-γ-AApeptides with a hybrid backbone and low molecular weight. The heterogeneous backbone not only enhances chemodiversity, but also shows effective antimicrobial activity against Gram-positive bacteria and is capable of disrupting bacterial membranes and killing bacteria rapidly. Given their low molecular weight and ease of access via facile synthesis, they could be practical antibiotic agents.

2.
Environ Res ; 180: 108813, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31627158

RESUMO

Hydrometric information collected by monitoring networks is fundamental for effective management of water resources. In recent years, entropy-based multi-objective criterions have been developed for the evaluation and optimization of hydrometric networks, and copula functions have been frequently used in hydrological frequency analysis to model multivariate dependence structures. This study developed a dual entropy-transinformation criterion (DETC) to identify and prioritize significant stations and generate candidate network optimization solutions. The criterion integrated an entropy index computed with mathematical floor function and a transinformation index computed with copula entropy through a tradeoff weight. The best fitted copula models were selected from three Archimedean copula families, i.e., Gumbel, Frank and Clayton. DETC was applied to a streamflow monitoring network in the Fenhe River basin and two rainfall monitoring networks in the Beijing Municipality and the Taihu Lake basin, which covers different network classification, network scale, and climate type. DETC was assessed by the commonly used dual entropy-multiobjective optimization (DEMO) criterion and was compared with a minimum transinformation (MinT) based criterion for network optimization. Results showed that DETC could effectively prioritize stations according to their significance and incorporate decision preference on information content and information redundancy. Comparison of the isohyet maps of two rainstorm events between DETC and MinT showed that DETC had advantage of restoring the spatial distribution of precipitation.

3.
Oral Oncol ; 98: 141-146, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31586896

RESUMO

OBJECTIVES: This study aimed to validate the 8th edition of American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) TNM staging system for nasopharyngeal carcinoma (NPC) in non-endemic region. MATERIALS AND METHODS: We recruited 607 patients with histology-proven, previously untreated, non-metastatic NPC treated by intensity-modulated radiotherapy (IMRT) at our center. Harrell's concordance index (c-index) and Akaike information criterion (AIC) were applied to compare the prognostic discrimination between the 7th and 8th edition staging system. RESULTS: For T category, the local recurrence-free survival (LRFS) Kaplan-Meier curves of T1, T2 and T3 were well separated in the 8th edition; however, LRFS did not significantly differ between T3 and T4 (P = 0.166). Moreover, the 7th edition achieved higher c-index (0.702 [95% CI, 0.618-0.787] vs. 0.685 [95% CI, 0.604-0.767]) and lower AIC (766.1 vs. 770.8) than 8th edition for LRFS. With regard to N category, the 8th edition achieved higher c-index (0.796 [95% CI, 0.749-0.843] vs. 0.751 [95% CI, 0.696-0.805]) and lower AIC (1439.4 vs. 1471.9) for distant metastasis-free survival. In terms of overall stage, the 8th edition also had higher c-index (0.798 [95% CI, 0.753-0.844] vs. 0.721 [95% CI, 0.672-0.770]) and lower AIC (1963.9 vs. 2007.2) compared with the 7th edition for overall survival. Furthermore, interval validation by bootstrapping the sample randomly for ~100-1000 times also validated above findings. CONCLUSION: The 8th edition of AJCC/UICC TNM staging system achieved significantly better prognostic discrimination than the 7th edition with regard to N category and overall stage but not T category.

4.
Am J Infect Control ; 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31540834

RESUMO

BACKGROUND: Urinary catheterization, even of short duration, increases the risk of subsequent urinary tract infection (UTI). Whether the bacteria found on the surface of catheters placed for <3 days are associated with UTI risk is unknown. METHODS: We screened the biofilms found on the extraluminal surface of 127 catheters placed for <3 days in women undergoing elective gynecologic surgery, using targeted quantitative polymerase chain reaction and an untargeted 16S rRNA taxonomic screen. RESULTS: Using quantitative polymerase chain reaction, Enterococcus spp were found on virtually all catheters and lactic acid bacteria in most catheters regardless of duration, but neither genus was associated with UTI development during follow-up. Enterococcus, Streptococcus, and Staphylococcus were the most commonly identified genera in the taxonomic screen but were not associated with subsequent UTIs. Although the most common cause of UTI following catheter removal was Escherichia coli, detectable E coli on the catheter surface was not associated with subsequent UTIs. CONCLUSIONS: Our analysis does not suggest that the presence of bacteria on the surface of catheters placed for <3 days leads to subsequent UTIs. Other aspects of catheter care are likely more important than preventing bacterial colonization of the catheter surface for preventing UTIs following short-term catheter placement.

5.
Nat Commun ; 10(1): 4044, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31492850

RESUMO

Acute graft-versus-host disease (GVHD) remains a major obstacle for the wider usage of allogeneic hematopoietic stem cell transplantation (allo-HSCT), which is an effective therapy for hematopoietic malignancy. Here we show that caspase-11, the cytosolic receptor for bacterial endotoxin (lipopolysaccharide: LPS), enhances GVHD severity. Allo-HSCT markedly increases the LPS-caspase-11 interaction, leading to the cleavage of gasdermin D (GSDMD). Caspase-11 and GSDMD mediate the release of interleukin-1α (IL-1α) in allo-HSCT. Deletion of Caspase-11 or Gsdmd, inhibition of LPS-caspase-11 interaction, or neutralizing IL-1α uniformly reduces intestinal inflammation, tissue damage, donor T cell expansion and mortality in allo-HSCT. Importantly, Caspase-11 deficiency does not decrease the graft-versus-leukemia (GVL) activity, which is essential to prevent cancer relapse. These findings have major implications for allo-HSCT, as pharmacological interference with the caspase-11 signaling might reduce GVHD while preserving GVL activity.

7.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(7): 847-851, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31441408

RESUMO

OBJECTIVE: To investigate the relationship between plasma oxidative stress factors levels and organ damage parameters as well as prognosis in patients with sepsis. METHODS: A case-control study was conducted. Twenty-five patients admitted to surgical intensive care unit (ICU) of the First Affiliated Hospital of Sun Yat-sen University from March to December in 2016 and diagnosed as sepsis were enrolled as study subjects. Another 15 patients without sepsis admitted to surgical ICU in the same period were enrolled as controls. General demographic data, main diagnoses, acute physiology and chronic health evaluation II (APACHE II) score within 24 hours, clinical laboratory indicators [alanine aminotransferase (ALT), aspartate transaminase (AST), serum creatinine (SCr), blood urea nitrogen (BUN), C-reactive protein (CRP), procalcitonin (PCT), white blood count (WBC)] and oxidative stress indicators [superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO)] as well as length of ICU stay, total hospital stay and 28-day mortality were recorded. Spearman or Pearson correlation method was used to analyze the correlation between oxidative stress indicators and organ damage indicators as well as prognosis in patients with sepsis. Receiver operator characteristic (ROC) curve was plotted to evaluate the predictive value of oxidative stress indicators for 28-day mortality in patients with sepsis. RESULTS: The length of ICU stay in sepsis group was significantly longer than that in non-sepsis group [days: 7.0 (5.5, 11.0) vs. 4.0 (1.0, 11.0), P < 0.05], and AST, BUN, CRP, PCT, plasma MDA and NO levels were significantly higher than those in non-sepsis group [AST (U/L): 50.76±19.53 vs. 28.53±14.02, BUN (mmol/L): 9.99±5.26 vs. 6.97±4.32, CRP (mg/L): 109.28±42.79 vs. 60.33±46.68, PCT (µg/L): 5.4 (0.3, 24.0) vs. 0.6 (0.1, 1.5), MDA (ng/L): 488.31±76.68 vs. 399.30±50.23, NO (ng/L): 5.08±0.89 vs. 4.42±0.88, all P < 0.05]. There was no significant difference in gender, age, APACHE II score, total hospital stay, 28-day mortality, ALT, SCr, WBC or plasma SOD activity between the two groups. The correlation analysis between oxidative stress parameters and organ damage parameters as well as prognosis in patients with sepsis showed that MDA and NO were positively correlated with SCr (r value was 0.426 and 0.431, respectively, both P < 0.05), and there was a positive correlation between MDA and NO (r = 0.990, P < 0.01); plasma SOD activity was negatively correlated with 28-day mortality (r = -0.468, P < 0.05), while MDA and NO levels were positively correlated with 28-day mortality (r value was 0.598 and 0.611, respectively, both P < 0.01). ROC curve analysis showed that plasma SOD, MDA and NO levels had a good independent predictive effect on 28-day mortality, the area under ROC curve (AUC) was 0.816±0.087, 0.904±0.078 and 0.912±0.071, and the best cut-off value was 40.76% (sensitivity 68.4%, specificity 100%), 487.93 ng/L (sensitivity 83.3%, specificity 89.5%) and 5.31 ng/L (sensitivity 83.3%, specificity 89.5%), respectively. CONCLUSIONS: The plasma levels of oxidative stress factors in patients with sepsis are significantly increased, which is closely related to organ damage and poor prognosis. The plasma SOD, MDA and NO levels can be used as independent bio-marker to predict the 28-day mortality of patients with sepsis.


Assuntos
Estresse Oxidativo/fisiologia , Sepse/diagnóstico , Estudos de Casos e Controles , Humanos , Prognóstico , Sepse/metabolismo
8.
Clin Cancer Res ; 25(18): 5525-5536, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31152021

RESUMO

PURPOSE: APOBEC3-UNG imbalance contributes to hepatitis B virus (HBV) inhibition and somatic mutations. We aimed to explore the associations between hepatocellular carcinoma (HCC) risk and genetic polymorphisms predisposing the imbalance.Experimental Design: Genetic polymorphisms at APOBEC3 promoter and UNG enhancer regions were genotyped in 5,621 participants using quantitative PCR. HBV mutations (nt.1600-nt.1945, nt.2848-nt.155) were determined by Sanger sequencing. Dual-luciferase reporter assay was applied to detect the transcriptional activity. Effects of APOBEC3B/UNG SNPs and expression levels on HCC prognosis were evaluated with a cohort of 400 patients with HCC and public databases, respectively. RESULTS: APOBEC3B rs2267401-G allele and UNG rs3890995-C allele significantly increased HCC risk. rs2267401-G allele was significantly associated with the generation of APOBEC-signature HBV mutation whose frequency consecutively increased from asymptomatic HBV carriers to patients with HCC. Multiplicative interaction of rs2267401-G allele with rs3890995-C allele increased HCC risk, with an adjusted OR (95% confidence interval) of 1.90 (1.34-2.81). rs2267401 T-to-G and rs3890995 T-to-C conferred increased activities of APOBEC3B promoter and UNG enhancer, respectively. IL6 significantly increased APOBEC3B promoter activity and inhibited UNG enhancer activity, and these effects were more evident in those carrying rs2267401-G and rs3890995-C, respectively. APOBEC3B rs2267401-GG genotype, higher APOBEC3B expression, and higher APOBEC3B/UNG expression ratio in HCCs indicated poor prognosis. APOBEC-signature somatic mutation predicts poor prognosis in HBV-free HCCs rather than in HBV-positive ones. CONCLUSIONS: Polymorphic genotypes predisposing the APOBEC3B-UNG imbalance in IL6-presenting microenvironment promote HCC development, possibly via promoting the generation of high-risk HBV mutations. This can be transformed into specific prophylaxis of HBV-caused HCC.

9.
Nitric Oxide ; 90: 1-9, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170453

RESUMO

Currently, most antimicrobial topical treatments utilize antibiotics to prevent or treat infection at a wound site. However, with the ongoing evolution of multi-drug resistant bacterial strains, there is a high demand for alternative antimicrobial treatments. Nitric oxide (NO) is an endogenous gas molecule with potent antimicrobial activity, which is effective against a wide variety of bacterial strains. In this study, the potential for creating NO releasing creams containing the naturally occurring NO carrier, S-nitrosoglutathione (GSNO), are characterized and evaluated. GSNO is shown to have prolonged stability (>300 days) when mixed and stored within Vaseline at 24 °C. Further, enhanced proliferation of NO from GSNO using zinc oxide nanoparticles (ZnO) is demonstrated. Triggering NO release from the GSNO/Vaseline mixture using a commercial zinc oxide-containing cream exhibits first-order NO release kinetics with the highest %NO release over the first 6 h. Significant killing effects against S. aureus, S. epidermidis, and P. aeruginosa are demonstrated for the GSNO/Vaseline/ZnO cream mixtures in a proportional manner dependent upon the concentration of GSNO in the final mixture.

10.
Inorg Chem ; 58(18): 11903-11911, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31192594

RESUMO

Four hexanuclear circular helicates, {[Dy6L6(DMF)12]·6CF3SO3·12DMF}2 (1Dy), {[Gd6L6(DMF)12]·6CF3SO3·12DMF}2 (1Gd), [Dy6L6(DMF)10(H2O)2]·6ClO4·4H2O·10DMF (2Dy), and [Gd6L6(DMF)12]·6ClO4·2H2O·10DMF (2Gd), where DMF = N,N-dimethylformamide, were synthesized by employing a glutaratedihydrazide-bridged bis(3-methoxysalicylaldehyde) ligand (H2L) and characterized structurally and magnetically. Direct-current magnetic susceptibility studies indicated predominant weak antiferromagnetic exchange interactions among gadolinium analogues, which were quantified using the PHI software, giving J = -0.003 cm-1 with g = 2.00 for 1Gd and J = -0.001 cm-1 with g = 2.02 for 2Gd. Alternating-current magnetic susceptibility measurements indicated that complexes 1Dy and 2Dy show slow relaxation of magnetization behavior, further supported by theoretical calculations that also highlighted the toroidal arrangement of the magnetic moments.

11.
Cell Metab ; 30(3): 508-524.e12, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31204282

RESUMO

Fructose-1,6-bisphosphate (FBP) aldolase links sensing of declining glucose availability to AMPK activation via the lysosomal pathway. However, how aldolase transmits lack of occupancy by FBP to AMPK activation remains unclear. Here, we show that FBP-unoccupied aldolase interacts with and inhibits endoplasmic reticulum (ER)-localized transient receptor potential channel subfamily V, inhibiting calcium release in low glucose. The decrease of calcium at contact sites between ER and lysosome renders the inhibited TRPV accessible to bind the lysosomal v-ATPase that then recruits AXIN:LKB1 to activate AMPK independently of AMP. Genetic depletion of TRPVs blocks glucose starvation-induced AMPK activation in cells and liver of mice, and in nematodes, indicative of physical requirement of TRPVs. Pharmacological inhibition of TRPVs activates AMPK and elevates NAD+ levels in aged muscles, rejuvenating the animals' running capacity. Our study elucidates that TRPVs relay the FBP-free status of aldolase to the reconfiguration of v-ATPase, leading to AMPK activation in low glucose.

12.
Patient Educ Couns ; 102(10): 1875-1881, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31113688

RESUMO

OBJECTIVE: Three-dimensional printing may play an important role in patients' education. The objective of this study was to assess the effectiveness of personalized 3D printed models for increasing patient understanding of their medical condition and surgical plan. METHODS: Forty-five patients with degenerative lumbar diseases were randomized by block design into three groups: educational program presented by CT & MRI imaging (care-as-usual), 3D reconstructions, or personalized 3D printed models. Patients' level of understanding and satisfaction were evaluated by two questionnaires one day after education. RESULTS: Patients educated with personalized 3D printed models demonstrated an expanded level of understanding than patients educated with CT & MRI imaging (care-as-usual) (P < 0.05) and 3D reconstructions (P < 0.05). Personalized 3D printed models also resulted in a higher degree of patient satisfaction (P < 0.05). CONCLUSIONS: Personalized 3D printed models and 3D reconstructions can simplify and enhance understanding of lumbar anatomy, physiology, and patients' disease and surgical plan. Personalized 3D printed models also enhance patients' subjective satisfaction. PRACTICE IMPLICATIONS: Personalized 3D printed models for patient education are feasible and could be generalized for degenerative lumbar diseases.

13.
Int Urol Nephrol ; 51(8): 1451-1457, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31119517

RESUMO

PURPOSE: Peritoneal dialysis (PD) catheter implantation is necessary for patients with end-stage renal disease (ESRD) to maintain continuous ambulatory PD (CAPD). In this study, we aimed to introduce a half-percutaneous technique based on a modified trocar device for the placement of a PD catheter and to evaluate the safety and efficacy of this technique and its associated short-term postoperative outcomes. METHODS: Eighty-four ESRD patients who underwent PD catheter implantation with the half-percutaneous technique were recruited retrospectively between September 2016 and October 2017 from the Guangdong Provincial Hospital of Chinese Medicine. All catheter implantation procedures were performed by the same three nephrologists. The surgical protocol was described in detail, and the general intraoperative parameters and short-term complications were evaluated. RESULTS: All ESRD patients underwent successful PD catheterization with our novel technique. Neither conversion from this method to traditional open surgery nor major intraoperative complications were observed. The mean operative time was 20.8 ± 4.5 min, and the incision length was 2.28 ± 0.53 cm. The operative cost was CN ¥ 1762.45 (US $261), and the length of hospital stay was 7.5 ± 0.58 days. One patient (1.19%) showed leakage, and one patient (1.19%) experienced bleeding 2 weeks after the surgery. Catheter dysfunction due to catheter tip migration occurred in nine patients (10.7%) 2 weeks after the procedure, and the placement of the catheter was corrected with conservative treatment. No visceral injuries or PD-related infections were observed up to 4 weeks after the catheters were implanted. CONCLUSIONS: This half-percutaneous technique for PD catheter implantation appears to be a safe, effective and feasible procedure. This technique has the advantages of reduced surgical trauma, a shorter operative time and faster postsurgical recovery. In particular, this novel technique is easy for nephrologists to perform and therefore may help to promote and popularize PD treatment.

14.
J Biol Chem ; 294(22): 8872-8884, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31000631

RESUMO

Receptor-interacting protein kinase 3 (RIPK3) is a key regulator of programmed cell death and inflammation during viral infection or sterile tissue injury. Whether and how bacterial infection also activates RIPK3-dependent immune responses remains poorly understood. Here we show that bacterial lipids (lipid IVa or lipid A) form a complex with high mobility group box 1 (HMGB1), released by activated immune cells or damaged tissue during bacterial infection, and that this complex triggers RIPK3- and TIR domain-containing adapter-inducing IFN-ß (TRIF)-dependent immune responses. We found that these responses lead to macrophage death, interleukin (IL)-1α release, and IL-1ß maturation. In an air-pouch inflammatory infiltration model, genetic deletion of Ripk3, Trif, or IL-1 receptor (Il-1R), or monoclonal antibody-mediated HMGB1 neutralization uniformly attenuated inflammatory responses induced by Gram-negative bacteria that release lipid IVa and lipid A. These findings uncover a previously unrecognized mechanism by which host factors and bacterial components work in concert to orchestrate immune responses.

15.
Can J Cardiol ; 35(4): 490-500, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30935640

RESUMO

BACKGROUND: The IκB kinase (IKK) complex has been found to have critical functions in cancer and the immune system. In particular, IKKα, which is a member of the IKK complex, has been shown to influence the inflammatory response and malignant diseases. However, the role of IKKα in macrophages after myocardial infarction (MI) remains largely unknown. METHODS: Sham or MI operations were performed on macrophage-specific IKKɑ knockout (mIKKɑ-/-) mice and IKKɑflox/flox littermates. We ligated the left anterior descending coronary artery of the MI group and observed the results at 3, 7, and 30 days after MI. RESULTS: We discovered more severe cardiac dysfunction with reduced angiogenesis, fibrosis, and collagen deposition in mIKKɑ-/- than in IKKɑflox/flox. In addition, we also observed that macrophages in mIKKɑ-/- were easier to polarize to the M1 phenotype and expressed more proinflammatory factors than IKKɑflox/flox. Mechanistically, IKKα deficiency in macrophages inhibited the alternative nuclear factor-κB/RelB pathway and enhanced the MEK1/2/ERK1/2 pathway. CONCLUSIONS: Overall, our data identified IKKɑ in the heart as a novel mediator that protected the heart from a severe inflammatory response and attenuated ventricular remodelling after MI by negatively regulating macrophage polarization to the M1 phenotype. Therefore, IKKα may serve as a potential therapeutic target for treatment after MI.

16.
Inorg Chem ; 58(9): 5715-5724, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-30969114

RESUMO

Six tetranuclear DyIII complexes [Dy4(L)2(CH3OH)3(NO3)3]·3NO3·2H2O (1a), [Dy4(L)2(CH3OH)2(SCN)4(OCH3)2]·2CH3OH·2H2O (1b), {[Dy4(L)2(CH3OH)(SCN)6(CH3CN)]·3CH3OH·4CH3CN}2 (2a), [Dy4(L)2(CH3OH)2(SCN)6]·6CH3OH·2H2O (2b), [Dy4(L)2(CH3OH)2(SCN)4(OCH3)2]·5CH3OH·2H2O (3a), and [Dy4(L)2(CH3OH)(SCN)5(H2O)2]·SCN·4CH3OH·2H2O (3b) were structurally and magnetically characterized. The Dy1/Dy2 centers in these complexes are eight-coordinate and submitted to pseudo- D4d symmetry environments. It is noteworthy that the modulation of coordination terminal around Dy1/Dy2 centers induces distinct magnetic relaxation processes, switching from single relaxation (1b) to two-step relaxation (2b). All complexes show significant zero-field single-molecule magnet (SMM) properties with the exception of 3b, which only features the slow magnetic relaxation behavior under a zero dc field. Ab initio calculations substantiate that the excellent SMM property of complex 1b should mainly profit from strong ferromagnetic interactions between the individual DyIII ions, while different single-ion magnetism results in better SMM property of complex 3a than that of 3b.

17.
Acta Biomater ; 90: 112-121, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30980938

RESUMO

Nitric oxide (NO) releasing polymers have been widely applied as biomaterials for a variety of biomedical implants and devices. However, the chemical leaching of NO donors and their byproduct species is almost always observed during the application of polymers doped with NO donors, unless the donor is covalently linked to the polymer. Herein, we report the first NO releasing poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) fluorinated copolymer prepared by incorporating a fluorinated S-nitrosothiol as the NO donor. Under physiological conditions, the resulting polymeric films can release NO for 16 days. Importantly, due to both fluorine-fluorine and electrostatic charge interactions between the fluorinated NO donor and the PVDF-HFP copolymer, the total chemical leaching of the fluorinated NO donor and its disulfide product after 9 day was only 0.6% (mol%) of the initial amount of NO donor loaded into the film. These new NO release PVDF-HFP films exhibit antimicrobial and anti-biofilm activities against both Gram positive S. aureus and Gram negative P. aeruginosa strains. The NO-releasing PVDF-HFP polymer can also be coated on Teflon tubing to release NO under physiological conditions for extended time periods. This NO-releasing PVDF-HFP copolymer with greatly reduced chemical leaching could help enhance the biocompatibility and antimicrobial activity of various biomedical devices. STATEMENT OF SIGNIFICANCE: Fluoropolymers have been widely used in creating various biomedical implants and devices. However, nitric oxide (NO) release fluoropolymers have not been well studied to date. Additionally, in the application of biomaterials doped with NO donors, a significant amount of NO donors and their byproducts almost always leach into aqueous environment. We now report an NO releasing poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) fluoropolymer by incorporating a new fluorinated S-nitrosothiol. The NO release can last for 16 days under physiological conditions. The total chemical leaching was determined to be only 0.6 mol% of the initial S-nitrosothiol loaded. As expected, significant antimicrobial/anti-biofilm activities of the NO release PVDF-HFP film were observed against Gram positive S. aureus and Gram negative P. aeruginosa bacterial strains.

18.
Appl Environ Microbiol ; 85(10)2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30850432

RESUMO

Natural microbiota plays an essential role in flavor compounds used in traditional food fermentation; however, the fluctuation in natural microbiota results in inconsistency in food quality. Thus, it is critical to reveal the core microbiota for flavor compound production and to construct a synthetic core microbiota for use in constant food fermentation. Here, we reveal the core microbiota based on their flavor production and cooccurrence performance, using Chinese light-aroma-type liquor as a model system. Five genera, Lactobacillus, Saccharomyces, Pichia, Geotrichum, and Candida, were identified to be the core microbiota. The synthetic core microbiota of these five genera presented a reproducible dynamic profile similar to that in the natural microbiota. A Monte Carlo test showed that the effects of five environmental factors (lactic acid, ethanol, and acetic acid contents, moisture, and pH) on the synthetic microbiota distribution were highly significant (P < 0.01), similar to those effects on a natural fermentation system. In addition, 77.27% of the flavor compounds produced by the synthetic core microbiota showed a similar dynamic profile (ρ > 0) with that in the natural liquor fermentation process, and the flavor profile presented a similar composition. It indicated that the synthetic core microbiota is efficient for reproducible flavor metabolism. This work established a method for identifying core microbiota and constructing a synthetic microbiota for reproducible flavor compounds. This work is of great significance for the tractable and constant production of various fermented foods.IMPORTANCE The transformation from natural fermentation to synthetic fermentation is essential in constructing a constant food fermentation process, which is the premise for stably making high-quality food. According to flavor-producing and cooccurring functions in dominant microbes, we provided a system-level approach to identify the core microbiota in Chinese light-aroma-type liquor fermentation. In addition, we successfully constructed a synthetic core microbiota to simulate the microbial community succession and flavor compound production in the in vitro system. The constructed synthetic core microbiota could not only facilitate a mechanistic understanding of the structure and function of the microbiota but also be beneficial for constructing a tractable and reproducible food fermentation process.

19.
Electrophoresis ; 40(16-17): 2193-2203, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30815884

RESUMO

Fentanyl and morphine are opioid drugs as well as new psychoactive substances. Even originally introduced as efficient anesthetic drugs to relieve moderate-to-severe pain in clinic, the overdose of new synthetic opioids is currently a serious public health problem in numerous countries worldwide. The entire category of fentanyls has been included in the regulatory list in several countries. There is a great and urgent demand to rapidly recognize fentanyls and morphines in various samples. Here, we report an on-site surface-enhanced Raman spectroscopic method to classify fentanyls from morphines by the Raman spectroscopic signature of the molecular scaffold structure, with an assistance of principle component analysis algorithm. Moreover, by simple but fine-tuning approach of inorganic salt-induced aggregation of gold nanoparticles substrate, we achieved a selective detection of 10 ng/mL fentanyl from 2000-fold of heroin, the most common coexisting substance in chemical samples. Good differentiation of 50 ng/mL fentanyl from 10 000-fold morphine as a main metabolite of heroin in urine samples was also possible after a feasible pretreatment by StageTip procedures. Depending on different structures, the detection sensitivity of five fentanyls ranged from 50 to 2000 ng/mL.

20.
Spine (Phila Pa 1976) ; 44(14): 1025-1033, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30817736

RESUMO

STUDY DESIGN: This study is a systematic literature review and meta-analysis. OBJECTIVE: To evaluate the efficacy of tubular microdiscectomy (TMD) compared with conventional microdiscectomy (CMD) for lumbar disc herniation (LDH). SUMMARY OF BACKGROUND DATA: TMD has developed rapidly due to reduced tissue trauma by minimization of the required access to spine and disc herniation; however, CMD remains the standard of care for this patient group. To date, it remains debatable whether TMD is superior to CMD for LDH. METHODS: We performed a comprehensive database search of PubMed, EMBASE, and Cochrane Central Register of Controlled Trails for prospective randomized controlled trials (RCTs), through using Medical Subject Headings (MeSH) terms "microdiscectomy," "tubular microdiscectomy," "minimally invasive surgery," and "spinal disease." The retrieved results were last updated on March 15, 2018. Two independent investigators selected qualified studies, extracted indispensable data, assessed risk of bias of original papers. The Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach was used to grade quality of evidence. If I >50, the heterogeneity is considerable. RESULTS: Four RCT studies (total n = 605), involving 610 individuals with a follow-up period of no less than 12 months, were selected for further review. We assessed these studies as low overall risk of bias. There was low-quality evidence that TMD was superior to CMD considering postoperative Oswestry Disability Index scores (SMD, -3.43, 95% CI, -4.64 to -2.21, P < 0.00001). Compared with CMD, the TMD group exhibited significantly worse Short Form-36 physical function scores (SMD, -4.83, 95% CI, -8.94 to -0.72, P = 0.02). There were no significant differences in the visual analogue scale (P = 0.30), operative time (P = 0.68), dural tear (P = 0.52), and reoperation (P = 0.98). CONCLUSION: The benefits 1 year after TMD were similar to that of CMD. There was no significant difference in the incidence of reoperation and dural tear. LEVEL OF EVIDENCE: 1.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA