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1.
Environ Int ; 136: 105449, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31924580

RESUMO

Reservoirs play a vital role in the control and management of surface water resources. However, the long water residence time in the reservoir potentially increases the storage and accumulation of antibiotic resistant genes (ARGs). The full profiles and potential health risks of antibiotic resistomes in reservoirs are largely unknown. In this study, we investigated the antibiotic resistomes of water and sediment during different seasons in the Danjiangkou Reservoir, which is one of the largest reservoirs in China, using a metagenomic sequencing approach. A total of 436 ARG subtypes belonging to 20 ARG types were detected from 24 water and 18 sediment samples, with an average abundance of 0.138 copies/cell. The overall ARG abundance in the sediment was higher than that in the water, and bacitracin and vancomycin resistance genes were the predominant ARG types in the water and sediment, respectively. The overall ARG abundance in the dry season was higher than that in the wet season, and a significant difference in ARG subtype compositions was observed in water, but not in the sediment, between the different seasons. The potential horizontal gene transfer frequency in the water was higher than that in the sediment, and the ARGs in water mainly came from the sediment upstream of the reservoir. The metagenomic assembly identified 14 contigs as ARG-carrying pathogens including Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, and 3 of 14 carried virulence factors. Overall, the potential public health risks posed by resistomes in the water of the Danjiangkou Reservoir were higher in the dry season than in the wet season. Based on these results, strategies including sediment control and pathogen monitoring are suggested for water safety management in drinking water reservoirs.

2.
Nat Commun ; 11(1): 375, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953382

RESUMO

Lipids play a pivotal role in biological processes and lipid analysis by mass spectrometry (MS) has significantly advanced lipidomic studies. While the structure specificity of lipid analysis proves to be critical for studying the biological functions of lipids, current mainstream methods for large-scale lipid analysis can only identify the lipid classes and fatty acyl chains, leaving the C=C location and sn-position unidentified. In this study, combining photochemistry and tandem MS we develop a simple but effective workflow to enable large-scale and near-complete lipid structure characterization with a powerful capability of identifying C=C location(s) and sn-position(s) simultaneously. Quantitation of lipid structure isomers at multiple levels of specificity is achieved and different subtypes of human breast cancer cells are successfully discriminated. Remarkably, human lung cancer tissues can only be distinguished from adjacent normal tissues using quantitative results of both lipid C=C location and sn-position isomers.

3.
J Med Virol ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31944333

RESUMO

Enterovirus A71 (EV-A71) is one of the main pathogens causing hand, foot, and mouth disease (HFMD), and often causes diseases of the central nervous system. Early diagnosis is important to prevent EV-A71 outbreaks. The detection of serum immunoglobulin (Ig) M is widely used for the early diagnosis of EV-A71 in clinics, especially in rural areas. However, this technique requires the extraction of blood from children who have thin blood vessels and who might fear the use of needles. Therefore, difficulties in the detection process are often encountered. This study developed a noninvasive method to detect EV-A71-specific immunoglobulin (Ig) A in saliva for the diagnosis of EV-A71 infection. The sensitivity and specificity of IgA detection did not differ significantly compared with IgM detection. IgA antibodies were present in saliva for a relatively shorter period than IgM antibodies were present in serum. The sensitivity of IgA detection was higher than that of IgM detection for secondary EV-A71 infections. These results suggest that the detection of EV-A71-specific IgA in the saliva allows the effective early diagnosis of EV-A71 and may be suitable for detecting EV-A71 infections in children. This article is protected by copyright. All rights reserved.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31922384

RESUMO

As a new type porous material, metal-organic frameworks (MOFs) have been widely studied in gas adsorption and separation, especially in C2 hydrocarbons. Considering the stronger interaction between the unsaturated molecules and the metal sites, and the smaller molecule size of unsaturated molecules, the usual relationship of affinities and adsorption capacities among C2 hydrocarbons in most common MOFs is C2H2>C2H4>C2H6. Herein, a unique microporous metal-organic framework, NUM-7a (activated NUM-7), with a completely reversed adsorption relationship for C2 hydrocarbons (C2H6>C2H4>C2H2) has been successfully synthesized, which breaks the traditional concept of adsorption relationship of MOFs for C2 hydrocarbons. Based on this unique adsorption relationship, a green and simple one-step separation purification for a large amount of C2H4 can be achieved through selective adsorption of C2H6. In addition, NUM-7a also shows good selectivities in C2H2/CO2 and CO2/CH4.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31935834

RESUMO

Objectives: The aim of this study was to understand the willingness for downward referral among older adults who were hospitalized in the year before the survey and to explore its influencing factors. Methods: The sample was randomly selected by the multi-stage sampling method. A structural questionnaire was used to collect data from participants age 60 and above in Shandong, China, during August 2017. Data were analyzed by using descriptive statistics, one-way ANOVA, chi-square test, and multinomial logistic regression. Results: Of 1198 participants who were hospitalized in the year before the survey, 28.7% self-initiated downward referral, and 33.9% were willing to accept downward referral after a doctor's advice. Multinomial logistic regression results showed that self-rated health, treatment effect in primary medical institutions, preference for outpatient service, choice of inpatient service, general understanding of essential medicines, the cost of essential medicines after zero-markup policy, and satisfaction with essential medicines' reimbursement policy significantly correlated with older adults' willingness for downward referral. Conclusions: The proportion of older adults who self-initiated downward referral was less than one-third. Doctors' advice plays an important role in willingness for downward referral. More attention should be paid to improving the treatment effect of primary medical institutions, increasing the benefits of zero-markup policy, and ensuring a high reimbursement for the downward referral to work alongside doctors' advice.

6.
Sensors (Basel) ; 20(2)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936555

RESUMO

Multi-baseline (MB) phase unwrapping (PU) is a key step of MB synthetic aperture radar (SAR) interferometry (InSAR). Compared with the traditional single-baseline (SB) PU, MB PU is applicable to the area where topography varies violently without obeying the phase continuity assumption. A two-stage programming MB PU approach (TSPA) proposed by H. Yu. builds the link between SB and MB PUs, so many existing classical SB PU methods can be transplanted into the MB domain. In this paper, an extended PU max-flow/min-cut (PUMA) algorithm for MB InSAR using the TSPA, referred to as TSPA-PUMA, is proposed, consisting of a two-stage programming procedure. In stage 1, phase gradients are estimated based on Chinese remainder theorem (CRT). In stage 2, a Markov random field (MRF) model of PUMA is designed for modeling local contextual dependence based on the phase gradients obtained by stage 1. Subsequently, the energy of the MRF model is minimized by graph cuts techniques. The experiment results illustrate that the TSPA-PUMA method can drastically enhance the accuracy of the original PUMA method in the rugged area, and is more efficient than the original TSPA method. In addition, the noise robustness of TSPA-PUMA can be improved through adding more interferograms with different baseline lengths.

7.
Int J Cancer ; 146(2): 542-552, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31584197

RESUMO

Our previous researches have identified immunoevasive subtype muscle-invasive bladder cancer (MIBC) characterized with immune cells infiltration patterns. Our study explored the clinical significance, immunoregulatory role and therapeutic value of intratumoral IL22-producing cells in MIBC. Two hundred and fifty-nine formalin-fixed paraffin-embedded MIBC samples and 83 freshly resected MIBC tissues and 391 TCGA MIBC samples were retrospectively evaluated. Immunohistochemistry and flow cytometry were applied to identify immune cell infiltration and functional status. In vitro intervention studies were to test the therapeutic and predictive potential of IL22+ cells. Our data revealed patients with high IL22+ cells infiltration suffered poor overall survival and recurrence-free survival in both training and validation cohorts. Only pT2 patients of combined cohort with low IL22+ cells infiltration gained survival benefits from adjuvant chemotherapy (ACT) significantly. Besides, immune contexture featured with increased pro-tumor cells and immunosuppressive cytokines was identified in patients with high IL22+ cells density. The expression pattern of exhausted and effector markers in CD8+ T cells from high IL22+ cells subgroup indicated their dysfunctional status. Importantly, nivolumab showed tumor-killing efficacy in tumors with high IL22+ cells infiltration, and immunosuppressive contexture with CD8+ T cells exhaustion was abrogated in tumors treated with anti-IL22 antibody. In summary, IL22+ cells infiltration determined immunosuppressive contexture with CD8+ T cell dysfunction. Tumor-infiltrating IL22+ cells could be used as an independent marker to predict prognosis and ACT responses. IL22+ cells infiltration possessed the potential to be a favorable predictor for nivolumab application and IL22 blockade could be a novel therapeutic strategy in MIBC.

9.
Sci Adv ; 5(11): eaay0855, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31803840

RESUMO

Soft robotics may enable many new technologies in which humans and robots physically interact, yet the necessary high-performance soft actuators still do not exist. The optimal soft actuators need to be fast and forceful and have programmable shape changes. Furthermore, they should be energy efficient for untethered applications and easy to fabricate. Here, we combine desirable characteristics from two distinct active material systems: fast and highly efficient actuation from dielectric elastomers and directed shape programmability from liquid crystal elastomers. Via a top-down photoalignment method, we program molecular alignment and localized giant elastic anisotropy into the liquid crystal elastomers. The linearly actuated liquid crystal elastomer monoliths achieve strain rates over 120% per second with an energy conversion efficiency of 20% while moving loads over 700 times the elastomer weight. The electric actuation mechanism offers unprecedented opportunities toward miniaturization with shape programmability, efficiency, and more degrees of freedom for applications in soft robotics and beyond.

10.
Blood Adv ; 3(23): 3962-3967, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31805192

RESUMO

Therapy-related acute myeloid leukemia and myelodysplastic syndromes (t-AML/t-MDS) are secondary hematologic malignancies associated with poor prognosis, warranting insights into their predisposing conditions and cells of origin. We identified patients with myeloma who developed t-AML/t-MDS and analyzed their stem and progenitor cells collected years before the onset of secondary disease. We demonstrate that aberrant stem cells with high CD123 expression can be detected long before the onset of overt leukemia. Rigorous sorting, followed by targeted sequencing, resulted in ultradeep functional depth of sequencing and revealed preexisting mutant hematopoietic stem cell (HSC) clones, mainly harboring TP53 mutations, that became the dominant population at the time of leukemic presentation. Taken together, these data show that HSCs can act as reservoirs for leukemia-initiating cells many years before the onset of myeloid leukemia.

11.
Fetal Pediatr Pathol ; : 1-6, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31805817

RESUMO

Background: Chromosome reciprocal translocations are frequently occurring structural rearrangements observed in humans. Although individuals with balanced reciprocal translocations tend to be clinically normal, they have an increased risk of reproductive failure, miscarriage and abnormal phenotype.Casereport: A 14 days old neonate was found to have a 46,X,der(Y)t(Y;18)(q12;q11)pat karyotype causing multiple dysmorphisms and death within one month. The proband inherited from his father(carrier) an abnormal Y chromosome with Yq deletion of regions (q12-qter) and an 18q duplication of regions (q11-qter), resulting in a severe clinical phenotype similar to Edwards syndrome (Trisomy 18 syndrome).Conclusion: These findings expand our current knowledge of the mutation spectrum of Y-autosomal translocations associated with dysmorphosis.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31842316

RESUMO

OBJECTIVE: This study aims to explore the determinants of general self-efficacy (GSE) among young-old elderly, with focus on examining the gender difference of general self-efficacy. METHODS: Data were collected from the 2017 Survey of the Shandong Elderly Family Health Service, which was conducted by Shandong University. T-test was used to examine the gender difference in GSE. Univariate models and adjusted multiple linear regression model were used to explore the determinants of GSE by gender. RESULTS: The females' GSE score was lower than that of male participants (26.1 ± 8.1 vs. 28.7 ± 7.7), and there was a significant gender difference (t = 10.877, p < 0.001). Multiple linear regression model showed that some factors are common significant determinants of GSE such as age, education level, activity of daily living (ADL), self-rated health, mental health, personality, and whether participants have intimate friends and interpersonal relationships. Hypertension and frequent communication with children were specific determinants of GSE among male young-old. Personal income was a specific determinant of female participants. CONCLUSION: Some influencing factors of GSE in both genders are identical, the others are different. More attention should be paid for the poor young-old females, young-old males with hypertension, and disabled young-old people.

13.
Bioresour Technol ; 299: 122598, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31869628

RESUMO

The H2-assisted biogas upgrading approach has recently attracted much interest as a low-cost and environmentally friendly alternative to commonly used ex-situ/ physiochemical biogas upgrading techniques. However, most studies conducted to date have been limited to anaerobic solid-waste treatment characterized by flocculant sludge and low organic loading rates (OLR). In an attempt to expand its application to high-rate anaerobic wastewater treatment, an innovative two-stage up-flow anaerobic sludge blanket reactor system was employed using anaerobic granular sludge. We found that the CH4 content of product gas was consistently >90% and that H2 and CO2 concentrations stayed below 5%, even when OLR was increased from 1 to 5 g L-1 d-1 and H2 feeding rates were increased from 0.13 to 0.63 g L-1 d-1. We were also able to show that CO (5-10%) in H2-rich syngas didn't inhibit methanogenesis or had significant impact on microbial community structure, suggesting that H2-assisted biogas upgrading with H2-rich syngas is feasible.

14.
Macromol Biosci ; : e1900331, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31856396

RESUMO

Polymer nanoparticulate drug delivery systems that respond to reactive oxygen species (ROS) and glutathione (GSH) simultaneously at biologically relevant levels hold great promise to improve the therapeutic efficacy to cancer cells with reduced side effects of chemo drugs. Herein, a novel redox dual-responsive amphiphilic block copolymer (ABP) that consists of a hydrophilic poly (ethylene oxide) block and a hydrophobic block bearing disulfide linked phenylboronic ester group as pendant is synthesized, and the DOX loaded nanoparticles (BSN-DOX) based on ABPs with varied hydrophobic block length are fabricated for DOX delivery. The self-immolative leaving reaction of phenylboronic ester triggered by extracellular ROS and the cleavage of disulfide linkages induced by intracellular GSH both lead to rapid DOX release from BSN-DOX, resulting in an on-demand DOX release. Moreover, BSN-DOX show better tumor inhibition and lower side effects in vivo compared with free drug.

15.
Nature ; 576(7787): 433-436, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31853082

RESUMO

With few exceptions1-3, polydispersity or molecular heterogeneity in matter tends to impede self-assembly and state transformation. For example, shape transformations of liquid droplets with monodisperse ingredients have been reported in equilibrium4-7 and non-equilibrium studies8,9, and these transition phenomena were understood on the basis of homogeneous material responses. Here, by contrast, we study equilibrium suspensions of drops composed of polydisperse nematic liquid crystal oligomers (NLCOs). Surprisingly, molecular heterogeneity in the polydisperse drops promotes reversible shape transitions to a rich variety of non-spherical morphologies with unique internal structure. We find that variation of oligomer chain length distribution, temperature, and surfactant concentration alters the balance between NLCO elastic energy and interfacial energy, and drives formation of nematic structures that range from roughened spheres to 'flower' shapes to branched filamentous networks with controllable diameters. The branched structures with confined liquid crystal director fields can be produced reversibly over areas of at least one square centimetre and can be converted into liquid crystal elastomers by ultraviolet curing. Observations and modelling reveal that chain length polydispersity plays a crucial role in driving these morphogenic phenomena, via spatial segregation. This insight suggests new routes for encoding network structure and function in soft materials.

16.
J Orthop Surg Res ; 14(1): 467, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881917

RESUMO

BACKGROUND: Posterior percutaneous endoscopic lumbar discectomy (PELD) has become a preferred procedure for the treatment of simple lumbar disc herniation (LDH) but has rarely been reported for distant upward migration. The purpose of this research was to investigate the feasibility, safety, clinical efficacy and technical points of posterior PELD combined with the vertical anchoring technique (VAT) for the treatment of LDH with distant upward migration. METHODS: Thirteen patients with distant upward migrated LDH who underwent posterior PELD combined with the VAT from March 2016 to May 2018 were selected. Among these cases, the herniated disc was located at L3/4 in 2 patients, L4/5 in 9 patients and L5/S1 in 2 patients. The operative time, length of hospital stay and postoperative complications were recorded. The visual analogue score (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores and modified MacNab criteria were used to assess surgical efficacy. RESULTS: All 13 patients underwent successful surgery. We compared the VAS, ODI and JOA scores before and after surgery. The differences were statistically significant (P < 0.05). According to the modified MacNab criteria, 10 patients were assessed as "excellent", 2 patients were assessed as "good" and 1 patient was assessed as "fair" at the last follow-up. The rate of satisfactory outcomes was 92.3%. CONCLUSION: Posterior PELD combined with the VAT is a safe and feasible procedure for the treatment of LDH with distant upward migration and represents a new approach for this type of surgery.

17.
Aging (Albany NY) ; 11(21): 9846-9861, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699955

RESUMO

Iron homeostasis is critical for maintaining normal brain physiological functions, and its mis-regulation can cause neurotoxicity and play a part in the development of many neurodegenerative disorders. The high incidence of iron deficiency makes iron supplementation a trend, and ferric citrate is a commonly used iron supplement. In this study, we found that the chronic oral administration of ferric citrate (2.5 mg/day and 10 mg/day) for 16 weeks selectively induced iron accumulation in the corpus striatum (CPu), substantia nigra (SN) and hippocampus, which typically caused parkinsonism phenotypes in middle-aged mice. Histopathological analysis showed that apoptosis- and oxidative stress-mediated neurodegeneration and dopaminergic neuronal loss occurred in the brain, and behavioral tests showed that defects in the locomotor and cognitive functions of these mice developed. Our research provides a new perspective for ferric citrate as a food additive or in clinical applications and suggests a new potential approach to develop animal models for Parkinson's disease (PD).

18.
J Cancer ; 10(24): 6114-6123, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31762821

RESUMO

Background: This systematic review and meta-analysis aims to provide comparative and quantitative data about immune checkpoint inhibitor (IMM) and targeted therapy (TAR) in this work. Methods: A literature search was performed with PubMed, Embase, PMC database, and Web of Science databases to identify relevant studies. Hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS), and odds ratios (ORs) for overall response rate (ORR) were estimated. Results: Eighteen manuscripts were ultimately utilized for indirect comparisons. In general, both TAR and IMM can prolong the PFS either by monotherapy, combination therapy with chemotherapy or adjuvant therapy. BRAF inhibitor monotherapy showed superiority over anti-CTLA-4 in OS (HR: 1.28, 95%CI: 0.93-1.75) and best ORR (OR: 12.57, 95%CI: 6.63-23.82), as well as longer PFS (HR: 1.63, 95%CI: 1.00-2.67) and higher best ORR (OR: 3.29, 95%CI: 1.94-5.55) compared with anti-PD-1. However, MEK inhibitor monotherapy showed no priority. When combined with chemotherapy, anti-CTLA-4 showed marginally advantages over MEK inhibitor in OS (HR: 0.68, 95%CI: 0.44-1.03), however no advantage in PFS (HR: 1.12, 95%CI: 0.76-1.64), or ORR (OR: 1.78, 95%CI: 0.70-4.49). For post-operational melanoma patient, adjuvant TAR and adjuvant IMM showed no difference in OS (HR: 1.14, 95%CI: 0.82-1.58) or PFS (HR: 1.20, 95%CI: 0.79-1.83). Moreover, the high-rate adverse events and underlying diseases should be considered during the application of those agents. Conclusions: For the unresectable late-stage melanoma, IMM may be a better choice for the combined treatment with chemotherapy. If the chemotherapy is not tolerable for patients, BRAFi involved TAR can be considered.

19.
J Hazard Mater ; : 121507, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31690505

RESUMO

Aerogels that derived from biomass have long been attractive as absorbents for oil clean-up. However, it remains a significant challenge to prepare fully bio-based oil absorbents that combines fast oil/water separation capacity, adequate mechanical robustness and easy recyclability through green and facile strategy. Inspired by the fascinating structure of wood, here we report a highly porous and anisotropic bio-based aerogel by taking advantage of the directional freezing technology, followed by a freeze-drying and silylation process. Due to the directional growth of ice crystals along the vertical direction, a special spring like morphology was obtained, which is mainly composed of well aligned low-tortuosity channels that seamlessly connected to bottom layer. Superior mechanical properties that allow for high mechanical compressing and fast elastic recovery were consequently acquired. Moreover, the silylated CS aerogel displays a rather high oil absorption capacity of 63 g g-1, together with excellent recyclability via simple hand squeezing. By virtue of such hierarchical morphology, a device that could continuously separate oil from water was successfully designed. Given the natural abundance of raw material as well as the easy processability, this work would lay solid foundation for further fabrication of bio-based oil absorbents toward low-cost, high-performance and large-scale commodities.

20.
ACS Nano ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31714733

RESUMO

Tumorous vasculature plays key roles in sustaining tumor growth. Vascular disruption is accompanied by internal coagulation along with platelet recruitment and the resulting suppression of oxygen supply. We intend to artificially create this physiological process to establish the mutual feedback between vascular disruption and platelet-mimicking biotaxis for the cascade amplification of hypoxia-dependent therapy. To prove this concept, mesoporous silica nanoparticles are co-loaded with a hypoxia-activated prodrug (HAP) and a vessel-disruptive agent and then coated with platelet membranes. Upon entering into tumors, our nanotherapeutic can disrupt local vasculature for tumor inhibition. This platelet membrane-coated nanoplatform shares the hemorrhage-tropic function with parental platelets and can be persistently recruited by the vasculature-disrupted tumors. In this way, the intratumoral vascular disruption and tumor targeting are biologically interdependent and mutually reinforced. Relying on this mutual feedback, tumorous hypoxia was largely promoted by more than 20-fold, accounting for the effective recovery of the HAP's cytotoxicity. Consequently, our bioinspired nanodesign has demonstrated highly specific and effective antitumor potency via the biologically driven cooperation among intratumoral vascular disruption, platelet-mimicking biotaxis, cascade hypoxia amplification, and hypoxia-sensitive chemotherapy. This study offers a paradigm of correlating the therapeutic design with the physiologically occurring events to achieve better therapy performance.

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